cpmplaint about the registration at UNISA Port Elizabeth

I had the most terrible experience with UNISA Port Elizabeth this year. I app**** for studying for the 2019 academic year first semester. My application was successful and I was sent an SMS to accept an offer to study there for 2019 first semester. After registering my modules and paying a registration fee of R1530 I couldn't log in to the student portal even though I had successfully registered. I went to their premises to enquire about this and they told me that my application was not successful because they claim that I hadn't paid my application fee even though I had paid the application fee of R105 on September 2018 but since I had lost the receipt I could not argue this successfully. They told me I would have to wait till second semester to proceed with my studies. This is an inconvenience and a complete waste of time because they should not allowed me to register if my application was not successful.